Abstract27Al NMR studies of AlCl3 solutions in diethyl ether reveal the presence of AlCl4 at high concentrations. This ion can also be recognized besides AlCl3·OR2 at low temperature in dilute solutions, while at 25 °C a single signal is observed, which represents the average of all species in solution. More extensive dissociation of AlCl3 results in tetrahydrofuran. The main species in equilibrium with one another are AlCl3·2THF, AlCl-4 and AlCl2(THF)+2.Nearly quantitative dissociation to yield AlCl-4 and [AlClL5]2+ occurs in dilute solutions of AlCl3 in monoglyme (L reprents one oxygen donor atom); at higher concentration an adduct AlCl3·L with Al in a tetrahedral environment is also present. This trend towards extensive dissociation is also observed in the solutions of AlCl3 in diglyme and triglyme. Relative peak areas are in agreement with the formation of a 1:1 electrolyte [AlCl2L4]+AlCl-4 in diglyme, whereas additional dissociation into [AlClL5]2+ and AlCl-4 occurs in triglyme.
